1. Field of the Invention
This invention relates to a valve or curb service box assembly for buried service valves (Minneapolis pattern), operated from ground level.
2. Description of Related Art
Current valve or curb service boxes connect to service valves buried below ground level. These valves control the flow through a buried pipeline connected to the valve. Access to the buried valve is by means of a conduit or soil pipe used to accept a wrench of sufficient length to extend down through the pipe for the coupling of the wrench to the valve nut, and then turned to operate the valve for an open or closed effect.
Some valves or curb service boxes have an extension rod already coupled to the valve nut which rod extends a short distance upwards inside the service box. This allows for the actuation of the valve in the same manner as those using a long wrench but allows the use of a similar, but shorter type of wrench. Both of these known service boxes require the removal of a plug or cap from the top of the service box and the lowering of a wrench into the conduit or soil pipe to connect to the valve nut. This method can prove to be difficult if debris has entered the conduit or soil pipe and does not allow the wrench to extend to the valve nut. Broken or removed plugs and tops allow foreign material, such as debris, water, rocks, etc, to enter the conduit or soil pipe passage and restrict the entrance and connection of the wrench to the valve nut. With service boxes of this type, unauthorized persons may remove the plug or top and actuate the valve nut and replace the plug or top, and the controlling authority would not be aware of the action taken.
Currently known telescoping curb service boxes have an approximate adjustment length of one (1) foot vertically. Any upward force applied to the top of the curb box, after installation, may result in damage to the service box, buried valve, and piping. This can cause installation difficulty for the buried pipe and valve when trying to maintain proper expansion depth, as top ground conditions change. The need to obtain different length of curb service box systems to accomplish any given installation is currently the standard.
In addition, locating a service line can prove to be virtually impossible if no tracing system has been installed, and the design of currently known boxes does not provide for any practical or effective means of locating the service line.
There is therefore a need for an improved valve or curb service box assembly for buried service valves which are operated from ground level to correct the above noted deficiencies of existing curb service box assemblies.